The Western Australian government caught 172 sharks , and killed 50 of the largest animals , as part of a culling program that has sparked anger among conservationists .

The three-month program , which ended last week , used baited lines attached to floating drums to catch sharks off popular beaches in Western Australia following a spate of fatal shark attacks in waters off the state in recent years .

The scheme , which was part of the state 's $ 20 million shark mitigation policy , allowed for tiger , bull and great white sharks measuring longer than 10 feet -LRB- 3 meters -RRB- hooked on the drum lines to be destroyed .

Some 50 tiger sharks longer than 10 feet were killed between January 25 and April 30 . The largest one , which measured 14.8 feet -LRB- 4.5 meters -RRB- , was caught in February off Perth 's Floreat beach .

Not the right culprits ?

But none of the creatures captured were great white sharks , the species believed to be responsible for most of the recent fatal attacks in Western Australia , which have left seven people dead in the past three years .

Under the program , another 14 sharks measuring less than 10 feet died on the drum line and four more were destroyed because they were too weak to survive , according to the government 's figures published Wednesday .

Western Australia 's Fisheries Minister Ken Baston hailed the shark mitigation policy a success , saying it was restoring confidence among beachgoers and contributing to research about shark behavior .

`` The human toll from shark attacks in recent years has been too high , '' Baston said in a statement released to the media .

`` While of course we will never know if any of the sharks caught would have harmed a person , this government will always place greatest value on human life , '' the minister said .

Conservationist 's nightmare

But the scheme has been criticized by environmentalists who say the sea predators should remain protected species .

`` Of the 172 sharks that were caught on the drum line , the majority were tiger sharks which have n't been involved in shark fatalities for decades in Western Australia , '' Sea Shepherd shark campaigner Natalie Banks told CNN .

More than 70 % of the creatures caught on the drum line were n't large enough to be considered a threat or were other animals , like stingrays , Banks said .

While monitoring the government program , Sea Shepherd found that sharks released alive were in a `` state of shock '' known as tonic immobility and sank to the ocean floor , she said .

Hi-tech initiative

As part of its shark research and protection policy , the Western Australian Department of Fisheries is working on a satellite-linked shark tagging program that allows beach safety authorities to know , through near real-time alerts , if a tagged shark is in the vicinity .

Under the three-month cull scheme , 90 sharks were tagged before being released alive . Other animals caught on the line were freed , including seven stingrays and a north-west blowfish .

Beach closures due to shark sightings were also down this year , according to government figures . There were 93 closures in 2013-14 , compared to 131 the previous season .

The Western Australian government is seeking approval to extend the program for three more years .

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Some 50 large sharks killed under culling scheme in Australia 's largest state

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Western Australia government says the program helps improve beach safety and adds to scientific research

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According to conservationists , there is no evidence the policy has been successful

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The Western Australia government wants to extend the program for three more years